516 COMPOSITAE 
Plants monocarpic, annual or biennial with a root. 
lants nearly or quite glabrous, chutes heads solitary or clustered 
at the ends of branches; sane aries loosely imbricate, mostly 
r- or ovate-lanceolate; rare on pene hills = flats in south- 
ern California. 253 lepis. 
Plants ga or less hat nop caulescent = sculesen s generally 
clusters that are conspicuously assed by Nabtendie leaves; 
phoilaries more pan less appr mostly lanceolate or 
ovate; widespread in western United eee gat Canada. 
Phyllaries not closely ak ig loosely imbricate and erect or more or less spreading 
above the appressed bas 
Pubescence irc aR and arachnoid, not viscidulous; heads not nodding. 
hy s ingens ‘loosely ascending, sometimes a little spreading, sometimes 
aoe appressed. (See also C. cymosum with phyllaries more or less 
ee a lar.) 
Si cla whitish, probably the outermost spreading in the head; phyl- 
laries not strongly graduated; biennial or Eo apa with taproot 
(and perhaps also rhizome-like roots); Coast Ranges of Califor 
north to Washin gton. ar: spe lion, 
Flowers deep pink to purplish rea in ti Bag fot ere 
pgs Depbarctry with rh os arp ee 
from California to Idaho. 
Phyllaries more or less widely spreading or refined above po anpressed base 
(or cee coed to the tip in C. cali cum var. bernardinum) ; 
dove white, lavender, or pink, the cubacatiet widely spreading in the 
ite ag “plants monocarpic, mostly biennials with taproots ore Bers Besos 
perennial i int. peworkes e). 
Phyllaries put id-t , subglabrescent, tipped by a short 
spin stly 1- Ler m. lon, 11. C. californicum. 
Phyllaries ssl more Parla catty and thickly arachnoid- A 
Heads usually broader than long, hemispheric; phyllarie ped by 
pad nes mostly 5-10 mm. long, the —. ‘phyllaries Bi re- 
flexed. 29 
Heads subglobose; spines on phyllaries wile me a mm. one the 
outer phylaiaa spreading or ascending. 
$3... utahense. 
and leaves viscidulous, as well a ; head 
clusters rat hous nodding in flower; outer cb, em pay sprea adin, 
or recurved above the appressed base; rare perennial plants along streams 
in areas of serpentine rock in the South Coast Ranges in California. 
Pubescence of stem 
or 
Outer phyllaries narrowly ovate, gradually narrowed to a ho spiny tip. 
33. C. campylon 
Outer phyllaries broadly ovate, abruptly — rid a short- aginiie tip. 
C. fontinale, 
Staion Seth ie and sometimes middle) mo i i th 
Fl ong or eaves red anil cee “lanate with a close, suede- like tomentum; rare plant of 
n California coastal dunes TS:-C; rhothophilum. 
vise nthe pink, or veddial: satel whitish; stems and leaves not lanate. 
Phyllaries _Coute er and middle) attenuate int 
nto long, stiff, yellow spines that exceed the inner phyl- 
laries; flowers straight in the head; rare plant of Wacney County, bade aed 
C. peckii. 
Phyllaries creed or 5 riny, the spines generally less t long; outermost flowers in 
the head re or less outwardly spreading; mostly Coaee: RB plants of California, Oregon, 
Washi wis 
Phyllaries conspicuously pectinate, the inner phyllaries chartaceous or scarious at the tip and 
gla estin ~ along the midvein below the tip; perennial “with rhizome-like a south- 
enon and northwestern Californ . C. acantho dont 
Phiilaries: rate i 
nconapiwonsy pectinate, not nisi 3 
or 
Phylla srl -spinos spines less than 5 mm. long; heads often pudding after anthesis; 
‘one cesentinie from Coos Bay, Oregon, to phen gs 
Tit. 
users — with spines 5 mm. long or longer; heads not nodding; monocarpic plants 
bp widely Spreading ea about the middle; a pee rose; plants of 
ually wet coastal s drewst 
Phyllaries appres ssed except ro ‘th spreading spinose tip; corollas teckedins -rose; plants 
of stream-banks in the San Joaquin Valley. 23. C. crassicaule. 
mS Cirsium arvénse (L.) Scop. Canada or Creeping Thistle. Fig. 5902. 
is L. Sp. Pl. 820. 1753. 
« FL. Carn, ed.:2:25126, 1772, 
Plants Peon; dioecious, perennial — erect shoots arising from widely creeping, borin 
roots ; stems mostly simple below and c mbosely branching above, 0.3-1.5 or 2 m. tall, 
winged or imes more or less inte i rrow decurrent latbaa “- ‘ 
leaves loosely clustered, oblong- or elliptic-oblanceolate, narrowed o a short, petiole-like 
_undulate or pi obed, spinose-bristl an toga Bes 1 teeth; go leaves 
liptic-obovate or ob! late, narrowed at base or the base amplexicaul, to 2 dm. lo cm. 
wide, shallow] deeply pinnately lobed or divided, the margins poimapetwietiy, the ‘to and 
divisions spine-tipped ; uppermost — reduced and sometimes bract-like; all leaves preheat 
above and —— or more or les pdhistcenesttns below ds 1.5-2.5 cm, long, short- 
stalked, solitary or in small ieriihel "chige rs that — an irre egular corymb; invo BfGe res o2 cm. 
long, subglobose to ate ; phyllaries numerous in many series, the qute Sake the pide 
srebeiecediate, both tipped by a rt, stiff, is spine ioaed hake. peat Cb id o! 
gins, the 
the 
inner linear-lanceolate with tip flattened and somewhat twisted ; corollas sirpiish, meses 
